In this R21, we are undertaking a 3-year randomized sham-controlled blinded study of acupuncture for the treatment of chronic insomnia. A secondary aim of the study is to explore the effect of acupuncture on hyperarousal, as measured by both heart rate variability (HRV) and quantitative EEG (QEEG) during polysomnography (PSG). We are requesting supplemental funds to add a 1-hour psychophysiological testing (PPT) protocol at baseline and end-of-intervention (EOI), which fits within the above specific aim. We are proposing to add PPT because: insomnia is associated with hyperarousal;acupuncture can result in a shift from sympathetic to parasympathetic predominance;this will provide us with a potentially useful mechanism to account for the clinical benefit of acupuncture for insomnia and potentially other conditions. Given the prominence of daytime symptoms among insomnia patients, our study would be strengthened by the inclusion of PPT in a laboratory setting. PUBLIC HEALTH RELEVANCE: Insomnia is a common and disabling condition associated with psychiatric and medical comorbidities and often persists despite currently available treatments. Acupuncture has been reported to benefit individuals with insomnia and can decrease hyperarousal. This blinded RCT will investigate the impact of a standardized acupuncture protocol on insomnia, daytime symptoms, and hyperarousal.